ACPI / device_sysfs: Change _SUN and _STA show functions error return to EIO

The error return from a sysfs show function is passed up through
the call chain and visible as the return from the read system call.
The show functions for the _STA and _SUN object currently return
-ENODEV. This patch changes the return to -EIO. ENODEV makes less
sense since the "device' exists or there wouldn't be a sysfs file.
Signed-off-by: NBetty Dall <betty.dall@hpe.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/device_sysfs.c

@@ -467,7 +467,7 @@ acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
 
 	status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun);
 	if (ACPI_FAILURE(status))
-		return -ENODEV;
+		return -EIO;
 
 	return sprintf(buf, "%llu\n", sun);
 }
@@ -496,7 +496,7 @@ static ssize_t status_show(struct device *dev, struct device_attribute *attr,
 
 	status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
 	if (ACPI_FAILURE(status))
-		return -ENODEV;
+		return -EIO;
 
 	return sprintf(buf, "%llu\n", sta);
 }